Dam.



PATENI'E'J) SEPT. 26, 1905.

. J. MEYERS.

DAM. AYPLIGATION FILED 13110.19, 1904.

2 SHEETS-SHEET 1.

'PATENTED SEPT. 26, 1,905,

. J; MEYBRS.

DAM. I

APPLICATION FILED DEO.19, 1904.

2 SHEETS-SHEET 2.

MENTO WITNESSES.-

UNITED STATES PATENT ornice.

WILLIAM J. MEYERS, OF FORT COLLINS, COLORADO. F

i DAM.

which the water above and upstream from the dam directly presses. I use the term cutoff wail to denotethat portion of the substructure whose purpose it is to preventor impede the underground escape of the waters of the reservoir or basin.

My invention briefly described consists in so shaping the sheet of the dam that every section of the water-face of said sheet normal to the crest of the damshall throughout the extent of said section be concave to the water of the reservoir, thus subjecting the said sheet along said section to tensile stresses dependent upon the degree of curvature of the water-face of said section and the depth of water lying thereon, which tensile stresses are resisted by suitably-disposed material of great tensile strength. Such material is at the base of the sheet suitably anchored and attached to the cut-off wall, and at the upper parts of the sheet the said material is suitably attached to beams substantially parallel to the crest of the dam, which beams, either alone or with the aid of arches lying in the plane of the load, transmittheload toposts suitably placed, by which posts the load is transmitted to the foundation of the structure. Where the base of the sheet and the plane of the anchorage are not tangent, as they ordinarily will not be, the resultant stress is carried to the foundation by suitably-disposed posts and arches, if such be neede To make the foregoing specification clearer, reference may be made to the drawings accompanying this specification, said' drawings being composed of five figures numbered 1, 2, 3, 4, and 5, respectively, placed upon two sheets, of which figuresnumbered 1, 2, and3 are upon Sheet I and figures numbered 4 and 5 are upon SheetII. Figurel represents the downstream, face of a portion of a dam constructed in the manner above briefly described. Fig. 2 shows a sectional view of such dam, the line YY in Fig. 1 being the trace of the cutting-plane. Fig. 3 shows another sec- Specification of Letters Patent.

Application filed December 19, 1904. $eriai-No. 237,426.

Patented Sept. 26, 1905.

tion, the line AB in Figs. 1 and 2 being the trace of the cuttingplane and the section being looked at'from beneath. In Fig. 2 the concave outline of the water-face of the section is circular. it will be advisable to makesuch outline that of the hydrostatic arch instead of a circular arc. Figs. 4 and 5 show the appearance of the dam in such case, Fig. 4 showing the downstream-face of a portion of a dam so constructed, and Fig. 5 showing a sectional view,

Under some circumstances the trace of the cutting-plane being the line In Fig. 2 the strands of the tensilely-stressed material embedded in and supporting the sheet are shownextending from a and t to e and from cand d to f-ct, b, c, and d denoting sections of the beams to which the upper ends of said strands are attached and e and f the beams to which the lower ends of said strands and the upper ends of the strands ef and git of the anchorage (lying, in the cut-off wall) are and transmitting its load to the posts P is a blind or concealed arch, being contained entirely within the sheet, and is denoted by the broken lined curve extending from Mr through if in Fig. 1. The arches supporting the beams b, c, and d are partially exposed and have their soflits shown at f and their springing-points at in in Fig. 1. The loads on these arches when the reservoir above the dam is filled have the directions shown approximately in Fig. 2 by the lines dd, 00, b7) and a vertical line extending do wnward. from a. These loads are transmitted to the foundation through the posts P and the walls w, Figs. 1, 2, and 3. The pull of the anchorage-strands eg and fit and that of the sheet-supporting strands ea, e12, f0, and fail will have a resultant whose direction is represented approximately in Fig. 2 by the line fd. If the soil adjacent to the cut-off wall m, Fig. 2, does not furnish sufiicient reaction to neutralize this resultant,

it must be provided for in the design of the wall 10, arches being-used in the plane of the resultant, if necessary, for concentrating this load upon the walls w. The underlying stratum forming the foundation or support for the entire structure (including the sub-" structure) must be suitably shaped to avoid any dangerous tendency to slide the structure downstream.

In Figs. 1, 2, and 3-the curve of the upstream face of the sheet is, as is above said, circular. This makes the tensile stress develattached. The arch supporting the beam at oped in the sheet and the supporting-strands (m, be, of, and (If proportional to the depth below the free surface of the fluid in the reservoir, thus requiring a greater number of such strands in the lower part of the sheet and a series of arches, one above the other at intervals from the bottom to the top, supporting the beams El 0 b, &c., for transmitting tangentially the loads to the supporting-posts P and walls 20, thence to the foundation. Under some circumstances it will be more satisfactory to have all tensile strands supporting the sheet carried to the top of the structure. In order that a tensile curve supporting hydrostatic pressure may be uniformly stressed throughout, its radius of curvature at any point must be inversely proportional to the distance of that point below the free surface of the fluid. In other words, the curve must be that known to engineers as the hydrostatic arch.

In Figs. 4: and 5 I have shown a dam in which the Water-face of the sheet is based upon the principle of the hydrostatic arch. In Fig. 5 the tensilely-stressed strand supporting the sheet is denoted by s. (t denotes the beam to which the upper end of s is fastened, which beam is supported by an arch whose sofiit is at 7', Figs. 4 and 5, and whose springing-point is at It, Figs. 4 and 5? The support or fastening of the lower end of the tensile strand 8 is substantially the same as is that in Fig. 2. (if necessary under the circumstances of the case) to transmit to the foundation the resultant of the stresses acting at 0, Fig. 5. Vhere necessary, an arch in the plane of the said resultant may be used for concentrating the resultant upon the posts 1. In this design the trilinearspace denoted by 11 in Fig. 5 is empty.

For the tensilely-stressed strands supporting the sheet steel wire will in most cases be 1' in Fig. 5 denotes a post inserted used and for the sheet concrete; but I do not limit myself to the use of any particular kind of matter nor to any particular 'ariety of curve; save that the curve be always in tension. \Vhere necessary for the prevention of deleterious contortion of the sheet when the reservoir is empty or only partially lilled, I shall use auxiliary cables or stiffening-trusses of any standard form, lying in planes normal to the crest of the dam. Sheet metal may also be used to resist tension.

\Vhat I claim as my invention, and desire to secure by Letters Patent of the United States, is

An improvement in dams for resisting lluidpressure, which said improvement consists of a substantially or sulliciently impervious sheet whose section in a plane normal to the crest of the dam is substantially e\er \;'\vhere concave to the impounded fluid, the said sheet being supported by tensilely-stressed material the tensile stresses wherein are substantially in planes normal to the crest of the dam, the load caused by the said tensile stresses being transmitted through the medium of beams or of arches or of beams and arches combined to posts or walls or posts and walls combined, by or through which the said lead is transmitted to the foundation of the structure, substantially as described in the foregoing specification, but without restriction of the class of curve to the circle, the hydrostatic arch or any other particular curve, save that the curve be substantially everywhere concave to the impounded lluid.

In testimony whereof I have hereto attached my signature in the presence of two subscribing witnesses.

\VM. J. MEYERS.

\Vitnesses:

B. H. l\IE.YER, EDWIN \V. Kenn, Jr. 

